CN111562106B

CN111562106B - Controllable variable load gear test bed based on CFRP transmission shaft

Info

Publication number: CN111562106B
Application number: CN202010439898.8A
Authority: CN
Inventors: 袁伟; 郭前建; 张立国; 于洁; 王志文; 董瑞春
Original assignee: Shandong University of Technology
Current assignee: Shandong University of Technology
Priority date: 2020-05-22
Filing date: 2020-05-22
Publication date: 2022-04-22
Anticipated expiration: 2040-05-22
Also published as: CN111562106A

Abstract

The invention discloses a controllable variable load gear test bed based on a CFRP transmission shaft, which mainly comprises a CFRP elastic shaft, a rigid shaft, a loading coupler, a magnetic powder brake, a gear box to be tested, a matched gear box, a peristaltic pump oil liquid circulating device, a belt transmission and auxiliary fixing device and an embedded industrial control all-in-one machine. Under the condition of a heavy-load high-speed test, the test bed realizes controllable loading on the gear to be tested based on the characteristics of the CFRP transmission shaft coupling machinery constant loading and the magnetic powder brake. The non-metallic material CFRP transmission shaft buffers and absorbs the working characteristics of shaking and combining the magnetic powder brake transmission, braking moment of torsion, the interference factor of the maximum reduction experiment. The test bed adopts a peristaltic pump circulating device to realize the non-stop uniform oil sample collection and detection in different time periods. The test bed adjusts parameters such as the rotating speed of a motor, the exciting current of a magnetic powder brake and the like through the embedded all-in-one machine, and establishes a functional relation between the exciting current and the gear load. The innovative method can improve the accuracy of experimental data and is convenient for obtaining the health state information of the gear.

Description

Controllable variable load gear test bed based on CFRP transmission shaft

Technical Field

The invention belongs to the technical field of gear state detection test beds, and particularly relates to a test bed for detecting the state of a gear, which is characterized in that a linear corresponding relation between a loading load and the loading of a gear box to be detected is established based on the transmission torque of a CFRP transmission shaft, a magnetic powder brake realizes the intervention of controllability, the test bed achieves the aim of accurate controllable continuous variable loading, oil of the gear box to be detected forms circulation by utilizing a peristaltic pump, the experimental gear box achieves the aims of uniform lubrication and wear particle deposition prevention, the health state data of the gear box can be accurately acquired based on the oil real-time monitoring technology, and the influence relation of the load characteristics on the healthy operation of the gear is researched.

Background

The gear transmission is to use the engaged gear pair to transmit movement and power, in the modern industrial equipment, the gear has the advantages of accurate transmission, high efficiency, strong transmission capability, long service life and the like, and is widely applied to the fields of modern industrial equipment and traffic, on the other hand, the superior performance of the CFRP composite material is popular in various industries and is applied to the fields of high-performance automobiles and aviation aircraft manufacturing, and the gear has the advantages of light weight and good fatigue resistance, particularly in the transmission shaft manufacturing industry, the gear is superior to a metal material in specific strength, specific modulus and fatigue resistance, and is a preferred material in the field of engineering tests. In the process of accurately detecting the load bearing capacity and the health evolution of the meshed gear, in order to reduce the influence of independent variables on experimental data as far as possible, different load characteristics are more accurately monitored, the influence on the working health state of the gear is particularly on the important occasion that a gear transmission system in a complex machine is difficult to maintain, the health state of the gear directly influences the industrial safety production and the working continuity of a large-scale unit, and therefore the use performance of the gear under different loads needs to be mastered in an experimental mode urgently. The influence of the residual deformation of the metal material on the service performance in the subsequent loading process is very complex, so that the running health state of the gear under different loads must be monitored by establishing a more accurate load function relationship, and therefore, the controllable variable load gear test bed based on the CFRP transmission shaft is particularly important, and has important value for the research on the health evolution process of the gear under different load characteristics.

At present, gear monitoring test beds have various forms, and the types of common gear test beds include a German FZG test bed and a American NASA test bed, but an elastic shaft applied to the test bed is made of a metal material, the metal material is taken as the elastic shaft and needs to be subjected to complicated heat treatment, on one hand, the elastic shaft made of the metal material has large mass, under the condition of a high-speed and heavy-load experiment, a motor and a gear box can generate large impact, the rotating inertia of the metal material is large, and the aspect of poor shock resistance and shock absorption capacity is highlighted, on the other hand, under the condition of heavy load, the elastic shaft made of the metal material has residual deformation stress due to displacement change among metal crystal grains, and on the contrary, the CFRP composite material has light mass, good toughness and excellent shock resistance and shock absorption performance. The magnetic powder brake has more and more outstanding performance effects on mechanical dynamometer loading and braking, and for realizing a more controllable and accurate loading mode, the magnetic powder brake loading mode is additionally arranged on the basis of the previous mechanical loading, so that the variable load in the running process is realized, the buffer and shock absorption effects are realized, the independent variable is controlled as much as possible, and the data accuracy is improved.

Disclosure of Invention

According to the invention, accurate detection of the health state of the gearbox is realized by improving the loading mode of the test bed, and because the transmission shaft can generate residual deformation and increase dynamic unbalance after deformation under the condition of high speed and heavy load, a linear elastic shaft with more excellent performance is required to be selected to establish the corresponding functional relationship between the loading load and the shaft deformation in order to avoid larger load accumulation error and material waste. The test bed can not only utilize the smoothness characteristic and the stable torque generated when the magnetic powder brakes are connected on the basis of the mechanical loading of the loading coupler to carry out controllable variable load loading, but also realize the buffer impact in the motor starting and speed changing processes in cooperation with a CFRP transmission shaft, and the double controllable variable load double-buffer shock absorption buffer of the two devices ensures that the test bed achieves smooth continuous and driving states. The oil circulating lubrication and sampling system is used for realizing uniform sampling of the wear state monitoring process of the gear box to be tested, eliminating irrelevant variables, achieving accurate and scientific evaluation of the health state of the gear box to be tested, ensuring the safety of the experimental process and realizing accurate monitoring of the wear state of the gear with load change in different time periods and a certain range.

The invention discloses a controllable variable load gear test bed based on a CFRP transmission shaft, which is characterized in that: the mechanical system comprises a transmission and auxiliary device, a loading device, a test device, a driving device, a peristaltic pump oil-liquid circulating device and a monitoring control device; the transmission and auxiliary device comprises: a CFRP transmission shaft [9], a rigid shaft [6], a drum-shaped tooth type coupling [10], a matched half coupling [13], a rigid coupling [14] and a fixing auxiliary device [7 ]; the loading device comprises: a differential loading coupler [8] and a magnetic powder brake [16 ]; the test device comprises: the gear box to be tested [2] and the matched gear box [11 ]; the driving device includes: a motor [3], a flat belt [4] and a belt wheel [5 ]; the peristaltic pump oil liquid circulating device: a peristaltic pump [12] and a rubber hose [1 ]; the monitoring control device includes: an embedded industrial control integrated machine [17 ].

The working principle of the mechanism is as follows: the CFRP transmission shaft is installed, so that the couplings with 6 holes uniformly distributed at the two tail ends of the transmission shaft are connected with the test gear box and the auxiliary gear box through flat keys through bolt nuts and other two half couplings, during loading, test loading is carried out on the differential loading coupling, the couplings are clamped in grooves of the two loading couplings through loading wrenches, gradient loading is carried out according to experimental requirements, every time when one graduation scale is superposed, two pairs of hinged holes on the two half loading couplings are superposed, hinged hole bolts are inserted into the two pairs of aligned holes, nuts are tightened, the loading wrenches are removed, and mechanical loading is realized (the loading torque corresponds to the deformation of the CFRP transmission shaft, and the loading torque applied by the loading couplings is applied to the meshing position of the test gear through the CFRP shaft all the time). The magnetic powder brake is connected with the mating gearbox shaft III through a rigid coupler, and the torque generated by the magnetic powder brake and the exciting current are in a linear relation in a certain range, so that the variable load torque can be transmitted and the buffer starting can be realized. The embedded industrial control all-in-one machine controls the magnetic excitation current and the motor speed, establishes the excitation current and gear load function relation according to experimental calibration data, and the peristaltic pump oil circulation device carries out oil closed loop circulation, extracts oil samples in different time periods, realizes the work of changing oil without stopping and disassembling the oil samples at any time, reduces the influence of impurity problems in the oil changing and oil sampling process, better embodies the safety and the environmental protection effect, and detects and assesses the gear meshing health state based on the oil sample quality and the abrasive particle characteristics.

The innovation points of the invention are as follows: a controllable variable-load gear test bed based on a CFRP transmission shaft utilizes the dynamic superior performance of a non-metal material transmission shaft CFRP compared with a metal material transmission shaft to minimize the rotational inertia of the CFRP transmission shaft after deformation, meanwhile, an electric motor and a gear are meshed to generate impact, and the vibration absorption and buffering of the CFRP material are superior to those of a metal material elastic shaft. Within a certain range, stable torque is generated according to the continuous braking characteristic of the magnetic powder brake under the action of exciting current, the test bed utilizes the magnetic powder brake to output adjustable torque on the basis of the constant mechanical loading of the loading coupler to carry out a controllable variable load loading experiment, and the double controllable loading modes of the two devices, the test bed has the damping and buffering characteristics, the test bed can be ensured to reach a smooth continuous braking state, the two gear boxes are in primary helical gear transmission, the functional relation between exciting current and load is favorably established, the oil circulating device with the peristaltic pump flexibility is combined, the oil change sampling work is realized without stopping, the influence on the state characteristics of the gear working process in the stopping process is avoided, more accurate and effective gear friction and wear monitoring data are obtained, and more scientific experimental data are provided for the research on the gear tribology state and the service life prediction.

Drawings

FIG. 1 is a schematic diagram of the overall three-dimensional structure of the present invention.

FIG. 2 is a schematic illustration of a mating gearbox.

Fig. 3 is a schematic view of a CFRP drive shaft mechanism.

In the figure: 1. a rubber tube; 2. a gear box to be tested; 3. an electric motor; 4. flattening the belt; 5. a pulley; 6. a rigid shaft; 7. a fixation aid; 8. a differential loading coupling; 9. a CFRP transmission shaft; 10. a drum-type tooth-shaped coupling; 11. a mating gear box; 12. a peristaltic pump; 13. a matched half coupling; 14. a rigid coupling; 15. a test bed rack; 16. a magnetic powder brake; 17. embedded industry control all-in-one.

Detailed Description

Embodiments of the present invention are further described below with reference to the accompanying drawings.

Referring to fig. 1, the general three-dimensional structure of the invention is schematically shown: the driving motor [3] is connected with a rigid shaft [6] through belt transmissions [4] and [5], one end of the rigid shaft is connected with a loading coupler [8] and then connected with the gear box [2] to be tested, and the other end of the rigid shaft is connected with a shaft II of a mating gear box [11] through a drum-shaped tooth type coupler [10] (see fig. 2); a shaft III of the pairing gear box is connected with a magnetic powder brake [16] through a flat key and a rigid coupler [14 ]; the matched gear box shaft I is connected with one end of a CFRP transmission shaft [9] through a flat key and a matched half coupling [13], the other end of the CFRP transmission shaft is also connected with a gear box to be tested through the matched half coupling (the CFRP transmission shaft [9] is aligned with 6 holes uniformly distributed in the outer ring of the matched half coupling [13], and is connected and installed through bolts and nuts which are connected with the differential loading coupling and have the same parameters, so that the process flow is reduced, and the controllable variable load gear test bed based on the CFRP transmission shaft can be formed stably and reliably (see fig. 3). And then the differential loading coupler [8] is loaded, the differential loading coupler [8] is also connected by bolts and nuts, the rotating speed of the motor [3] and the exciting current of the magnetic powder brake [16] are adjusted by the embedded industrial control integrated machine [17], the peristaltic pump [12] and the rubber hose [1] are connected and reasonably placed in a gear box to be tested, the lubricating mode of closed circulation oil supply is realized, the real-time oil sample collection is facilitated, and the gear state data post-processing health assessment is realized.

Claims

1. The invention discloses a controllable variable load gear test bed based on a CFRP transmission shaft, which is characterized in that: the device comprises a transmission and auxiliary device, a loading device, a testing device, a driving device, a peristaltic pump oil-liquid circulating device and a monitoring control device; the transmission and auxiliary device comprises: a CFRP transmission shaft [9], a rigid shaft [6], a drum-shaped tooth type coupling [10], a half coupling [13], a rigid coupling [14] and a fixing auxiliary device [7 ]; the loading device comprises: a differential loading coupler [8] and a magnetic powder brake [16 ]; the test device comprises: the gear box to be tested [2] and the matched gear box [11 ]; the driving device includes: a motor [3], a flat belt [4] and a belt wheel [5 ]; the peristaltic pump oil liquid circulating device: a peristaltic pump [12] and a rubber hose [1 ]; the monitoring control device includes: an embedded industrial control integrated machine (17); a shaft III of the pairing gear box is connected with the magnetic powder brake through a flat key and a rigid coupler [14 ];

in the initial stage of starting the motor, the test bed achieves buffer starting by utilizing the smooth connection characteristic of the magnetic powder brake and generating stable torque; on the basis of constant mechanical loading generated by a loading coupler, a magnetic powder brake with appropriate parameters is selected according to the allowable rotating speed in an experiment, the magnetic powder brake adjusts the exciting current to generate controllable output torque, and the double controllable variable load double buffering damping mode of the two devices ensures that the test bed achieves smooth continuous and driving states, and optimizes the health monitoring state of the gear box to be tested.

2. The controllable variable load gear test bed based on the CFRP transmission shaft according to claim 1, wherein: the driving motor [3] is connected with a rigid shaft [6] through a flat belt [4] and a belt wheel [5], one end of the rigid shaft is connected with a differential loading coupler [8] and then connected with a gear box [2] to be tested, and the other end is connected with a shaft II of a matched gear box [11] through a drum-shaped tooth type coupler [10 ]; the shaft I is connected with one end of a CFRP transmission shaft [9] through a flat key and a matched half coupling [13], and the other end of the CFRP transmission shaft is connected with a gear box to be tested through the matched half coupling to form a stable and reliable open-loop mechanical system and establish a function relation between experimental loading and gear loading; the peristaltic pump [12] and the rubber hose [1] are connected and placed in an opening at the upper part of the gear box to be tested, so that a lubricating mode of non-stop real-time sampling and closed circulation oil supply is realized.

3. The controllable variable load gear test bed based on the CFRP transmission shaft according to claim 1, wherein: the CFRP transmission shaft is made of a carbon fiber/epoxy resin composite material circular tube, important parameters such as the thickness and the angle of the CFRP transmission shaft are reasonably selected, the CFRP transmission shaft is made of a linear elastic material and has good toughness, and the CFRP transmission shaft and a rigid coupling with 6 holes uniformly distributed on an outer ring are reasonably combined under the action of a loading load, so that the diameter of the hollow shaft is set to be 5 +/-0.5 cm under the condition of meeting the maximum stress requirement according to the function relation of torque and the radius of the hollow shaft on the premise of ensuring reasonable safety experiments, and the reasonable assembly of a test bed is ensured; the test bed adjusts parameters such as the rotating speed of a motor, the exciting current of a magnetic powder brake and the like through an embedded all-in-one machine, an exciting current-load function relation is established, load change is only related to the exciting current of the brake and the fixed loading size of a differential loading coupler and is irrelevant to the rotating speed, the rotating speed is related to the fatigue life of an experimental gear, and the rotating speed is adjusted to shorten the experimental period; the CFRP transmission shaft made of the non-metallic material can absorb impact and vibration caused by the running of the test bed in the transmission process.